#include using namespace std; typedef signed long long ll; #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define FORR2(x,y,arr) for(auto& [x,y]:arr) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) template bool chmax(T &a, const T &b) { if(a bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;} //------------------------------------------------------- int N,M; int B[2020]; const ll mo=998244353; ll comb(ll N_, ll C_) { const int NUM_=400001; static ll fact[NUM_+1],factr[NUM_+1],inv[NUM_+1]; if (fact[0]==0) { inv[1]=fact[0]=factr[0]=1; for (int i=2;i<=NUM_;++i) inv[i] = inv[mo % i] * (mo - mo / i) % mo; for (int i=1;i<=NUM_;++i) fact[i]=fact[i-1]*i%mo, factr[i]=factr[i-1]*inv[i]%mo; } if(C_<0 || C_>N_) return 0; return factr[C_]*fact[N_]%mo*factr[N_-C_]%mo; } void solve() { int i,j,k,l,r,x,y; string s; cin>>N>>M; FOR(i,N) cin>>B[i]; ll ret=0; for(i=0;i<=M;i++) { int C[4]; FOR(j,N) { C[j]=B[j]-i; if(C[j]<0) break; } if(jM) continue; ll pat=comb(M,i)*comb(M-i,a)%mo*comb(M-i-a,b)%mo; for(int p1=0;p1<=min(a,C[1]);p1++) { int p2=C[2]-(C[1]-p1); if(p2<0) { p1+=-p2-1; continue; } if(p2>b) { break; } ret+=pat*comb(a,p1)%mo*comb(b,p2)%mo*comb(a-p1+b-p2,C[1]-p1)%mo; } } cout<